Even though they’ve been in our families since the dawn of man, our genes do not belong to us. They’ve been claimed by companies that hold patents on the DNA from our cells. Over the past 20 years, at least 41 percent of our genes have become the intellectual property of corporations. These patent claims contradict an intuitive sense that our DNA is no less ours than our lungs or kidneys. More importantly, these patents, covering thousands of human genes, restrict our doctors’ ability to look at our DNA and plan ahead for our medical treatment.